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981.
Y Takeda TL Andrew JM Lobez AJ Mork TM Swager 《Angewandte Chemie (International ed. in English)》2012,51(36):9042-9046
A thin-film transistor: An n-type polymer semiconductor, poly(2,3-bis(perfluorohexyl)thieno[3,4-b]pyrazine), was synthesized through a Pd-catalyzed polycondensation employing a perfluorinated multiphase solvent system. This is the first example of an n-type polymer semiconductor with exclusive solubility in fluorinated solvents. The fabrication of organic field effect transistors containing this new n-type polymer semiconductor is shown. 相似文献
982.
Osawa T Kajitani T Hashizume D Ohsumi H Sasaki S Takata M Koizumi Y Saeki A Seki S Fukushima T Aida T 《Angewandte Chemie (International ed. in English)》2012,51(32):7990-7993
Dipole bridge: Liquid-crystalline (LC) triphenylenes self-assemble columnarly into a hexagonal geometry with a wide-range 2D lattice correlation, for which distal and proximal dipole-dipole interactions are considered responsible. By virtue of the strong intercolumnar interaction, the LC columns of the triphenylene can spontaneously align homeotropically on the 12 different substrates examined (POM=polarized optical microscopy). 相似文献
983.
Chevrier R Daugas JM Gaudefroy L Ichikawa Y Ueno H Hass M Haas H Cottenier S Aoi N Asahi K Balabanski DL Fukuda N Furukawa T Georgiev G Hayashi H Iijima H Inabe N Inoue T Ishihara M Ishii Y Kameda D Kubo T Nanao T Neyens G Ohnishi T Rajabali MM Suzuki K Takeda H Tsuchiya M Vermeulen N Watanabe H Yoshimi A 《Physical review letters》2012,108(16):162501
We report on the spectroscopic quadrupole moment measurement of the 7/2(1)(-) isomeric state in (16)(43)S(27) [E*=320.5(5) keV, T(1/2)=415(3) ns], using the time dependent perturbed angular distribution technique at the RIKEN RIBF facility. Our value, |Q(s)|=23(3) efm(2), is larger than that expected for a single-particle state. Shell model calculations using the modern SDPF-U interaction for this mass region reproduce remarkably well the measured |Q(s)|, and show that non-negligible correlations drive the isomeric state away from a purely spherical shape. 相似文献
984.
Electrons and holes were injected selectively into poly-2,7-(9,9-dihexylfluorene) (pF) dissolved in a tetrahydrofuran (THF) and a 1,2-dichloroethane (DCE) solution, respectively, using pulse radiolysis. Transient absorption spectra of monoions of both signs revealed two bands attributable to formation of polarons, one in the visible region (pF+* at 580 nm, pF-* at 600 nm) and another in the near-IR region. Additional confirmation for the identification of pF+* and pF-* comes from bimolecular charge-transfer reactions, such as bithiophene-* + pF --> pF-* or pF+* + TTA --> +TTA+* (TTA = tri-p-tolylamine), in which known radical ions transfer charge to pF or from pF. Difference absorption spectra of pF chemically reduced by sodium in THF provided a ratio of absorbance of anions formed to bleaching of the neutral band at 380 nm. In conjunction with pulse-radiolysis results, the data show that each polaron occupies 4.5 +/- 0.5 fluorene units, most probably contiguous units. Extensive reduction of pF by sodium also revealed resistance to formation of bipolarons: excess electrons reside as separate polarons when two or more electrons were injected. Redox equilibria with pyrene and terthiophene by pulse radiolysis established reversible one-electron redox potentials of E0(pF+/0) = +0.66 V and E0(pF0/-) = -2.65 V vs Fc+/0. Together with the excited-state energy, these results predict a singlet exciton binding energy of 0.2 eV for pF in the presence of 0.1 M tetrabutylammonium tetrafluoroborate. This binding energy would increase substantially without an electrolyte. 相似文献
985.
Tamura H Chiba J Ito M Takeda T Kikkawa S Mawatari Y Tabata M 《Journal of colloid and interface science》2006,300(2):648-654
The formation reaction and the intercalation of adenosine triphosphate (ATP) were studied for hydrotalcite (HT), a layered double hydroxide (LDH) of magnesium and aluminum. Hydrotalcite with nitrate ions in the interlayer (HT-NO(3)) was formed (A) by dropwise addition of a solution of magnesium and aluminum nitrates (pH ca. 3) to a sodium hydroxide solution (pH ca. 14) until the pH decreased from 14 to 10 and (B) by dropwise addition of the NaOH solution to the solution of magnesium and aluminum nitrates with pH increasing from 3 to 10. The precipitate obtained with method B was contaminated with aluminum hydroxide and the crystallinity of the product was low, possibly because aluminum hydroxide precipitates at pH 4 or 5 and remains even after HT-NO(3) forms at pH above 8. With method A, however, the precipitate was pure HT-NO(3) with increased crystallinity, since the solubility of aluminum hydroxide at pH above and around 10 is high as dissolved aluminate anions are stable in this high pH region, and there was no aluminum hydroxide contamination. The formed HT-NO(3) had a composition of [Mg(0.71)Al(0.29)(OH)(2)](NO(3))(0.29).0.58H(2)O. To intercalate ATP anions into the HT-NO(3), HT-NO(3) was dispersed in an ATP solution at pH 7. It was found that the interlayer nitrate ions were completely exchanged with ATP anions by ion exchange, and the interlayer distance expanded almost twice with a free space distance of 1.2 nm. The composition of HT-ATP was established as [Mg(0.68)Al(0.32)(OH)(2)](ATP)(0.080)0.88H(2)O. The increased distance could be explained with a calculated molecular configuration of the ATP as follows: An ATP molecule is bound to an interlayer surface with the triphosphate group, the adenosine group bends owing to its bond angles and projects into the interlayer to a height of 1 nm, and the adenosine groups aligned in the interlayer support the interlayer distance. 相似文献
986.
Matsunami K Takamori I Shinzato T Aramoto M Kondo K Otsuka H Takeda Y 《Chemical & pharmaceutical bulletin》2006,54(10):1403-1407
Four new megastigmane glucosides, named macarangiosides A-D (2-5), together with mallophenol B, lauroside E, methyl brevifolin carboxylate, and hyperin and isoquercitrin as a mixture were isolated from the leaves of Macaranga tanarius (L.) MULL.-ARG. (Euphorbiaceae). Their structures were elucidated by spectroscopic and chemical analyses. Macarangioside A-C (2-4) and mallophenol B were galloylated on glucose moiety and possessed the potent 2,2-diphenyl-picrylhydrazyl (DPPH) radical-scavenging activity. 相似文献
987.
1-Siloxy-1-alkenylcopper species were generated by 1,2-Csp2-to-O silyl migration of the copper enolates of acyltriphenylsilanes. The alkenylcopper species reacted with methyl, benzyl, allylic, and tributylstannyl halides to give geometrically pure (Z)-enol silyl ethers. In the presence of Pd(0) catalyst, the cross-coupling of the alkenyl copper species with aryl and alkenyl iodides also proceeded to give the (Z)-enol silyl ethers with high stereoselectivity. 相似文献
988.
The enantioselective [2 + 2 + 2] cycloaddition of 1,6-diynes with alpha-methylene lactones and cyclic ketones gave various chiral spirocyclic compounds. The reaction proceeded with high enantioselectivity when the rhodium-xylylBINAP complex was used as a chiral catalyst. Not only exo-methylene cyclic compounds but also exo-methylene acyclic compounds could be used as coupling partners for diynes. The present protocol provides access to a new chiral library possessing a quaternary carbon center, including a spirocyclic system. 相似文献
989.
990.
Hamazawa RT Nishioka T Kinoshita I Takui T Santo R Ichimura A 《Dalton transactions (Cambridge, England : 2003)》2006,(11):1374-1376
Thiacalix[3]pyridine (Py3S3) consists of pyridines and bridging sulfur atoms producing a stable octahedral mononuclear Rh(II) complex [Rh(II)(Py3S3)2]2+ showing mutual Jahn-Teller effect, a metal based reversible redox couple of Rh(III/II) at 0.02 V vs. SCE and a g(perpendicular) > g(||) relationship in EPR measurements. 相似文献